US5146699A - Auger dredge specially adapted to removal of toxic sediment - Google Patents
Auger dredge specially adapted to removal of toxic sediment Download PDFInfo
- Publication number
- US5146699A US5146699A US07/802,548 US80254891A US5146699A US 5146699 A US5146699 A US 5146699A US 80254891 A US80254891 A US 80254891A US 5146699 A US5146699 A US 5146699A
- Authority
- US
- United States
- Prior art keywords
- shroud
- frame
- auger
- dredge
- dredging apparatus
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Fee Related
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Classifications
-
- E—FIXED CONSTRUCTIONS
- E02—HYDRAULIC ENGINEERING; FOUNDATIONS; SOIL SHIFTING
- E02F—DREDGING; SOIL-SHIFTING
- E02F3/00—Dredgers; Soil-shifting machines
- E02F3/04—Dredgers; Soil-shifting machines mechanically-driven
- E02F3/88—Dredgers; Soil-shifting machines mechanically-driven with arrangements acting by a sucking or forcing effect, e.g. suction dredgers
- E02F3/90—Component parts, e.g. arrangement or adaptation of pumps
- E02F3/92—Digging elements, e.g. suction heads
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
- Y10S—TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10S37/00—Excavating
- Y10S37/904—Vibration means for excavating tool
Definitions
- This invention relates to dredges and more particular to auger type dredges specially adapted to the removal of toxic sedimentary waste material.
- the broad object of the invention is to provide a dredge especially adapted to the removal of toxic sediment with a minimum of dislodged sediment or poisonous products, e.g. PAH, either to the atmosphere or into surrounding waters.
- a dredge especially adapted to the removal of toxic sediment with a minimum of dislodged sediment or poisonous products, e.g. PAH, either to the atmosphere or into surrounding waters.
- the foregoing object is achieved by the use of a dredge module carried at the remote end of a ladder whose opposite end is pivoted to a shallow draft barge.
- the module comprises a shrouded transverse auger and a wedge shaped substantially open frame fixed to the front of the auger shroud and serving to first cut and receive the dredged material and then direct it against the auger whereby the auger, instead of acting directly on the face of the material being dredged resulting in possible excessive turbidity, acts on the material after it has been preliminarily dislodged and partially comminuted by the frame.
- the auger is designed to further comminute the material as the auger delivers it to a centrally disposed dewatering and pumping means for transport to a remote site.
- a more specific object of the invention is to provide an auger type dredge especially adapted to the dredging of toxic sediment by the use of a wedge shaped frame into which the material is first received before reaching the auger.
- FIG. 1 is a side elevational view of a dredge barge showing in full lines a dredge ladder carrying a dredging module constructed in accordance with the invention and lowered to a working position, and in dashed lines the ladder and module raised to transport position;
- FIG. 2 is a top plan view of the barge of FIG. 1 showing the ladder in its raised transport position;
- FIG. 3 is an enlarged side elevational view of the ladder of FIGS. 1 and 2;
- FIG. 4 is a top plan view of the ladder of FIG. 3;
- FIG. 5 is an enlarged horizontal cross sectional view taken substantially on the line 5--5 of FIG. 3;
- FIG. 6 is a vertical cross sectional view taken substantially on the line 6--6 of FIG. 5;
- FIGS. 7a and 7b are horizontal change-position views, partly in plan and partly in section, showing the sludge pump of the present invention
- FIG. 8 is an enlarged broken elevational view of a part of the side of the dredge module of the present invention.
- FIG. 9 is an enlarged horizontal cross sectional view taken substantially on the line 9--9 of FIG. 8 and showing one form of vibration isolation connector connecting the frame to the auger shroud;
- FIG. 10 is a vertical side elevation partly in phantom and partly schematic showing counterweights which may be used with the dredge module of the invention.
- the numeral 10 refers to a shallow draft dredge barge having a slot 12 therethrough to accommodate a dredge ladder 14 pivoted at its inner end 16 to the closed end of the slot 12 and carrying at its remote end a dredge module generally designated by the numeral 18.
- the ladder is raised and lowered by conventional sheaves and falls generally indicated in FIG. 1 by the numeral 20.
- the solid lines in FIG. 1 show the ladder and module in working position and the dashed lines show these members in raised transport position.
- the dredge module 18 comprises an auger dredge 22 and a wedge shaped frame 23.
- the auger dredge 22 comprises a shroud 24 having closed end walls 26, 28 and a substantially closed arcuate rear wall 30 having an open front 32.
- Journaled to the respective end walls 26, 28 of the shroud are the opposed ends of an auger shaft 34 carrying oppositely threaded auger blades 36, 38, at least a part of each of which is connected to the shaft by radial, helically spaced spokes 39 whose function is later described.
- An hydraulic motor 40 carried by the end wall 28 drives the shaft 34 in a direction to cause material engaged by the blades 36, 38 to be propelled towards a central region 42 of the shroud into which extends the flared end 44 of a passage 46 encompassing a transfer auger or feed screw 48 carried by a shaft 50 and driven in a proper direction by an hydraulic motor 52 to transfer material from the central region 42 of the shroud into a vertical passage 54 (FIG. 6) leading to the bottom of an inlet chamber 56 of a double acting, positive displacement pump generally indicated by the numeral 58 and hereinafter described in detail.
- the wedge shaped frame 23 of the dredge module is open at its rear end 60 (FIG. 6) and has a pair laterally spaced vertical, outwardly flaring side walls 62, 64 (FIG. 5) whose upper and lower edges 66, 68 converge forwardly whereby the upper and lower faces 69, 70 of the frame terminate in a laterally extending cutting edge member 72 carrying a plurality of forwardly extending, laterally spaced digging teeth or tines 74.
- the frame 23 is constructed and arranged that when the module is in its operative position as generally shown in full lines in FIG. 1, the plane of the lower face 70 of the frame is substantially horizontal while the plane of the upper face 69 extends angularly upwardly and rearwardly from the cutting edge member 72.
- Rear horizontal laterally extending vertically spaced frame members 76, 78 define with the rear edges 79 of the frame side plates 62, 64 the rear opening 60 of the frame which is of substantially the same size as the open front 32 of the shroud.
- the frame member includes various flat structural member 82, best seen in FIG. 5, which are joined together with the side plates 62, 64 rear frame members 76, 78 and front cutting edge member 72 to form a rigid structure of great strength.
- Covering the upper and lower faces of the frame are screens 83, 84, respectively, and extending upwardly from the upper edges 66, 68 of the side plates 62, 64 are forwardly sloping outwardly flaring guide flanges 85.
- the frame 23 carries on the outer face of each side plate 62, 64 a vibrator 86 of known construction comprising a housing 88 in which is pivotally journaled a vertical shaft 90 carrying an eccentrically mounted weight 92.
- the shaft 90 is driven by an hydraulic motor 94 to cause the eccentric weight to impart to the frame lateral vibrations as indicated by the double edge arrow 96 in FIGS. 4 and 9.
- the frame is connected to the shroud by vibration damping means 97 comprising a plurality of transversely spaced horizontal flanges 96 and 98 mounted on vertical structural members 100, 102, fixed to the front end of the shroud 24 and to the rear end of the frame 23, respectively.
- the respective flanges have transversely spaced vertical apertures 104 therethrough and screwed into these apertures are coil springs 106 as clearly seen in FIG. 9.
- These flanges and springs constitute the sole connection between the frame and shroud with the springs effectively isolating the auger portion 22 of the module from the frame portion 23.
- the double acting positive displacement sludge pump 58 is of known construction and comprises a pair of pump pistons 106, 108 (FIG. 7a and b) which are operated in opposite directions by hydraulic cylinders 110, 112 whereby when one pump piston, say piston 106, is being retracted in the direction of arrow 114 to receive in its cylinder dredged material being crowded into the pump inlet chamber 56 by the feed screw 48 (FIGS.
- the other piston 108 is being extended in the direction of arrow 116 to drive the charge of material previously received in its cylinder into an oscillatable goose-necked conduit 118 whose inlet end is moved by suitable linkage (not shown) in a coordinated manner with the hydraulic cylinders 110, 112 from outlet, as shown in FIG. 7a, to the other, as shown in FIG. 7b, pump pistons 106, 108.
- the outlet of the goose-necked conduit has a swivel connection 120 with the inlet of a ladder-carried dredge pipe 122 having a conventional swivel connection 124 with the remainder 126 of the dredge pipe leading from the barge 10 to a remote disposal site.
- the outer end of the ladder is provided with a pair of laterally spaced arms 128 which pivotally journal stub shafts 130 carried by the side walls 26, 28 of the shroud 24.
- Extending rearwardly from the shroud are a pair of laterally spaced fins 132 (FIGS. 4 and 8) each pivotally receiving one end of a pair of hydraulic cylinders 134 whose opposite ends are pivotally connected to the ladder.
- the closed rear wall of the shroud is slotted as at 136 in FIG. 5, and welded to the exterior of the flared part 44 of the transfer passage is an arcuate plate 138 concentric with the rear wall 30 of the shroud and which interiorly covers the slot 136 for the maximum range of movement of the module 18 from its position of FIG. 6 to its upper dotted line position 18' as shown in FIG. 1.
- the dredge barge 10 is suitably positioned for straight ahead movement. It may have side sheaves (not shown) receiving parallel lines (not shown) anchored ahead of and to the rear of the barge and acting as guide lines to restrain the barge from sluing as it advances into the tar pond.
- the forward advance of the barge may be controlled by a line 140 (FIG. 1) leading from a winch 142 to an anchor (not shown) secured ahead of the barge.
- the ladder Prior to the initial cut the ladder is lowered to a position where the module will enter the material to be dredge substantially entirely beneath the surface 146 of the material as shown in FIG. 1.
- the vibrators 86 are energized to vibrate the frame laterally to assist in this and to break off small substantially solid undissolved pieces of the material being dredged while the barge is advanced forwardly. As the module is moved the chunks enter the frame through the screens 83, 84 until the frame is filled with broken chunks of the material being dredged. That state is determined by suitable sensors (not shown). As the barge continues to advance the material in the frame is crowded against the auger blades 36, 38 at which point the dredge operator in the control house 144 on the barge energizes the auger shaft 34 to force by the auger blades 36, 38 material crowded against them to the central region 42 of the shroud.
- the dredged material being moved in the module has a maximum solids concentration due to the fact that the module, being substantially submerged in the material being dredged, is substantially sealed by that material from the ingress of water disposed in the region being dredged.
- the blade spokes 39 aid in comminuting or pulverizing the chunks to a size which can be handled by the positive displacement pump 58.
- the pulverized material reaching the central region 42 of the shroud and transferred therefrom by the feed screw 48 is in a fluidic or flowable condition while being mostly solid which is suitable for pumping only by a positive displacement pump such as pump 58.
- the comminuted dredged material is delivered by the feed screw 48 to the inlet chamber 56 of the pump 58 at a rate 40 to 50% greater than the capacity of the sludge pump. The material thus crowded into the inlet chamber 56 is compressed to positively feed the intake of the positive displacement pump.
- the module will make several passes through the material each time being lowered to a depth wherein during dredging the module is substantially covered by the material being dredged. After all but a shallow layer of the material has been dredged in one path the barge will be laterally repositioned and will continue this process until only a shallow layer of sediment remains over the entire bottom.
- the ladder is elevated to its fully raised position and the hydraulic cylinders 134 for controlling the angle of the dredge module with respect to the ladder are disconnected from the rearwardly extending fins 132 and are replaced by counterweights 146 connected to the module by a rod 148 passing through the holes in the fins 132.
- the weights ar selected to counter-balance the module in a manner enabling it to follow the contours of the bottom as it collects the final shallow layer. This is known as the clean-up mode of the module.
- the upper screen may be as much as 90 % occluded as shown schematically in FIG. 10, by a plate 150 bolted to the upper edges of the side plates as schematically shown in FIG. 10. With the upper screen about 90% closed off, it may be desirable to close about 10% of the lower screen shown schematically by the plate 152 in FIG. 10.
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- Engineering & Computer Science (AREA)
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- Mining & Mineral Resources (AREA)
- Civil Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Structural Engineering (AREA)
- Ship Loading And Unloading (AREA)
Abstract
Description
Claims (13)
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US07/802,548 US5146699A (en) | 1991-12-05 | 1991-12-05 | Auger dredge specially adapted to removal of toxic sediment |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US07/802,548 US5146699A (en) | 1991-12-05 | 1991-12-05 | Auger dredge specially adapted to removal of toxic sediment |
Publications (1)
Publication Number | Publication Date |
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US5146699A true US5146699A (en) | 1992-09-15 |
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US07/802,548 Expired - Fee Related US5146699A (en) | 1991-12-05 | 1991-12-05 | Auger dredge specially adapted to removal of toxic sediment |
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Cited By (15)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US5651200A (en) * | 1995-12-06 | 1997-07-29 | The United States Corps Of Engineers As Represented By The Secretary Of The Army | Debris exclusion devices for an augerhead type hydraulic dredge system |
US6178670B1 (en) * | 1996-01-06 | 2001-01-30 | Rotech Holdings Limited | Underwater mining apparatus |
US20040010947A1 (en) * | 2002-07-19 | 2004-01-22 | Hutchinson Robert J. | Excavation system employing a jet pump |
US6755701B2 (en) | 2002-05-20 | 2004-06-29 | Wilco Marsh Buggies And Draglines, Inc. | Amphibious vehicle with submersible capacity |
US20050147472A1 (en) * | 2003-12-29 | 2005-07-07 | Alexander Samuel R. | Disposal of accumulated waste solids from processing of titanium-bearing ores |
US20060123671A1 (en) * | 2004-12-14 | 2006-06-15 | Cornelis Heuvelman | Cutter suction dredge |
WO2008062219A1 (en) | 2006-11-24 | 2008-05-29 | Ray Drabble | Seabed organic material relocating apparatus |
US20080172911A1 (en) * | 2007-01-24 | 2008-07-24 | Victor Joseph Buhr | Fine Sediment Removal Attachment for a Dredge |
US20110042284A1 (en) * | 2009-06-24 | 2011-02-24 | Richard John Phillips | Dredging apparatus |
CN102220773A (en) * | 2011-03-21 | 2011-10-19 | 吴平平 | Shallow dredging device for cutter suction dredger |
EP2484838A1 (en) * | 2011-02-08 | 2012-08-08 | Egon Prexl | Excavator method |
US20150086389A1 (en) * | 2011-09-06 | 2015-03-26 | Weir Canada Inc. | Pumping system |
US20150184358A1 (en) * | 2012-07-27 | 2015-07-02 | Nautilus Minerals Pacific Pty Ltd | Self Cleaning Collection Apparatus and Method |
USD740331S1 (en) * | 2012-09-12 | 2015-10-06 | Lännen Mce Oy | Dredger |
USD740330S1 (en) * | 2012-09-12 | 2015-10-06 | Lännen Mce Oy | Dredger |
Citations (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2178265A (en) * | 1938-09-21 | 1939-10-31 | Peterson Isaac | Hydraulic shovel dredge |
US3440742A (en) * | 1965-12-08 | 1969-04-29 | Albert S Goldstein Jr | Multiple motor dredge |
US4312762A (en) * | 1980-01-25 | 1982-01-26 | Blackburn Curtis D | Method and apparatus for removing sediment or other flowable solid material from a bed underlying a body of water |
US4839061A (en) * | 1988-06-13 | 1989-06-13 | Manchak Frank | Method and apparatus for treatment of hazardous material spills |
US4934874A (en) * | 1987-02-21 | 1990-06-19 | Saarbergwerke Ag | Mobile pumping installation |
US5027533A (en) * | 1990-01-11 | 1991-07-02 | Harbor Branch Oceanographic Institution Inc. | Vibratory shellfish harvesters and methods |
-
1991
- 1991-12-05 US US07/802,548 patent/US5146699A/en not_active Expired - Fee Related
Patent Citations (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2178265A (en) * | 1938-09-21 | 1939-10-31 | Peterson Isaac | Hydraulic shovel dredge |
US3440742A (en) * | 1965-12-08 | 1969-04-29 | Albert S Goldstein Jr | Multiple motor dredge |
US4312762A (en) * | 1980-01-25 | 1982-01-26 | Blackburn Curtis D | Method and apparatus for removing sediment or other flowable solid material from a bed underlying a body of water |
US4934874A (en) * | 1987-02-21 | 1990-06-19 | Saarbergwerke Ag | Mobile pumping installation |
US4839061A (en) * | 1988-06-13 | 1989-06-13 | Manchak Frank | Method and apparatus for treatment of hazardous material spills |
US5027533A (en) * | 1990-01-11 | 1991-07-02 | Harbor Branch Oceanographic Institution Inc. | Vibratory shellfish harvesters and methods |
Cited By (22)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US5651200A (en) * | 1995-12-06 | 1997-07-29 | The United States Corps Of Engineers As Represented By The Secretary Of The Army | Debris exclusion devices for an augerhead type hydraulic dredge system |
US6178670B1 (en) * | 1996-01-06 | 2001-01-30 | Rotech Holdings Limited | Underwater mining apparatus |
US6755701B2 (en) | 2002-05-20 | 2004-06-29 | Wilco Marsh Buggies And Draglines, Inc. | Amphibious vehicle with submersible capacity |
US20040010947A1 (en) * | 2002-07-19 | 2004-01-22 | Hutchinson Robert J. | Excavation system employing a jet pump |
US6860042B2 (en) * | 2002-07-19 | 2005-03-01 | Walker-Dawson Interests, Inc. | Excavation system employing a jet pump |
US20050147472A1 (en) * | 2003-12-29 | 2005-07-07 | Alexander Samuel R. | Disposal of accumulated waste solids from processing of titanium-bearing ores |
US20060123671A1 (en) * | 2004-12-14 | 2006-06-15 | Cornelis Heuvelman | Cutter suction dredge |
US20100126047A1 (en) * | 2006-11-24 | 2010-05-27 | Ray Drabble | Seabed organic material relocating |
US8091255B2 (en) * | 2006-11-24 | 2012-01-10 | Ray Drabble | Seabed organic material relocating |
WO2008062219A1 (en) | 2006-11-24 | 2008-05-29 | Ray Drabble | Seabed organic material relocating apparatus |
US7721472B2 (en) * | 2007-01-24 | 2010-05-25 | J.F. Brennan Co., Inc. | Fine sediment removal attachment for a dredge |
US20080172911A1 (en) * | 2007-01-24 | 2008-07-24 | Victor Joseph Buhr | Fine Sediment Removal Attachment for a Dredge |
US20110042284A1 (en) * | 2009-06-24 | 2011-02-24 | Richard John Phillips | Dredging apparatus |
EP2484838A1 (en) * | 2011-02-08 | 2012-08-08 | Egon Prexl | Excavator method |
WO2012107180A1 (en) * | 2011-02-08 | 2012-08-16 | Egon Prexl | Tix dredging method |
CN102220773A (en) * | 2011-03-21 | 2011-10-19 | 吴平平 | Shallow dredging device for cutter suction dredger |
US20150086389A1 (en) * | 2011-09-06 | 2015-03-26 | Weir Canada Inc. | Pumping system |
US9937444B2 (en) * | 2011-09-06 | 2018-04-10 | Weir Canada Inc. | Pumping system |
US20150184358A1 (en) * | 2012-07-27 | 2015-07-02 | Nautilus Minerals Pacific Pty Ltd | Self Cleaning Collection Apparatus and Method |
US9739032B2 (en) * | 2012-07-27 | 2017-08-22 | Eda Kopa (Solwara) Limited | Self cleaning collection apparatus and method |
USD740331S1 (en) * | 2012-09-12 | 2015-10-06 | Lännen Mce Oy | Dredger |
USD740330S1 (en) * | 2012-09-12 | 2015-10-06 | Lännen Mce Oy | Dredger |
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Legal Events
Date | Code | Title | Description |
---|---|---|---|
AS | Assignment |
Owner name: ELLICOTT MACHINE CORPORATION, MARYLAND Free format text: ASSIGNMENT OF ASSIGNORS INTEREST.;ASSIGNOR:LIPFORD, KEITH W.;REEL/FRAME:005942/0926 Effective date: 19911203 |
|
AS | Assignment |
Owner name: ELLICOTT MACHINE CORPORATION INTERNATIONAL, MARYLA Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNOR:ELLICOTT MACHINE CORPORATION;REEL/FRAME:006743/0734 Effective date: 19930927 |
|
AS | Assignment |
Owner name: MARYLAND INDUSTRIAL DEVELOPMENT FINANCING AUTHORIT Free format text: SECURITY INTEREST;ASSIGNOR:ELLICOTT MACHINE CORPORATION INTERNATIONAL;REEL/FRAME:006773/0439 Effective date: 19931112 Owner name: CORESTATES BANK, N.A., MARYLAND Free format text: SECURITY INTEREST;ASSIGNOR:ELLICOTT MACHINE CORPORATION INTERNATIONAL;REEL/FRAME:006773/0439 Effective date: 19931112 |
|
AS | Assignment |
Owner name: ELLICOTT MACHINE CORPORATION INTERNATIONAL Free format text: TERMINATION OF SECURITY AGREEMENT;ASSIGNOR:CORESTATES BANK, N.A.;REEL/FRAME:007414/0229 Effective date: 19941214 |
|
REMI | Maintenance fee reminder mailed | ||
LAPS | Lapse for failure to pay maintenance fees | ||
FP | Lapsed due to failure to pay maintenance fee |
Effective date: 19960918 |
|
STCH | Information on status: patent discontinuation |
Free format text: PATENT EXPIRED DUE TO NONPAYMENT OF MAINTENANCE FEES UNDER 37 CFR 1.362 |